Northwest
Africa 4819

Northwest
Africa
Find: 2007
Mass: 234 g

Achondrite
(lunar, feldspathic breccia)

History
and physical characteristics: A single 234 g crusted stone
was purchased in Rissani, Morocco in 2007. The
crust is fresh, dark gray to black crusted areas and vermillion to light
brown in abraded to weathered areas, some areas show melt bubbles and flow.
A network of thin fractures is filled with weathering products.

Petrography (T.
Bunch and J. Wittke, NAU; A. Irving, UWS): This
stone is very dark, well indurated, and is fine-grained with few clasts
that exceed one mm in diameter. No evidence of flow orientation was
observed. NWA 4819 is a regolith breccia and has two unusual
characteristics for a lunar sample: (1) a relatively large amount of
homogeneously distributed fine-grained metallic nickel-iron (2 wt. %) and
troilite (1.5 wt. %) and (2) a large population of pyroxene fragments. Most
lithic clasts follow the ferroan anorthositic trend and include
anorthosites, fine-grained anorthositic norites, gabbros, and troctolites,
in addition to shock melt clast. K-rich glass, and spherules. No intact
basaltic clasts were observed and all clasts are
crushed to some extent.